1. Field of the Invention
This invention relates to a data carrier and a method for producing same. The data carrier is in particular an identification card or payment card with at least one layer that forms a card body and a transparent outer layer laminated thereon, as well as at least one planar security element that is provided with security information, in particular holographic or kinegraphic information.
2. Description of the Related Art
Data carriers of the type described above are used as, among other things, identification cards or payment cards or as xe2x80x9cdata pagesxe2x80x9d in passports. Reference is made to the prior art as described in DE 3048733 C, DE 3151407 C, DE 4134539 A, DE 3840729 C and EP 0,230,497 A. U.S. Pat. No. 5,658,411 discloses a method for the manufacture of a laminate that can be an identification card. In that case, a protective layer is laminated onto a security element. The security element can contain holographic information and is on the uppermost layer of a card body. A technician skilled in the art will also be aware that the protection of such data carriers against counterfeiting can be significantly increased by a kinegraphic or holographic security element. Such security elements are applied to the data carrier by means of a hot press stamping process, for example. In that case, the security elements are vapor-deposited on the underside of a strip-format carrier film. These security elements are transferred by means of a heated stamp in the hot stamping process. After the hot stamping, the strip-format carrier film is pulled off. The vapor-deposited layer is an extraordinarily thin layer of metal, e.g. aluminum. It has now been shown that such security elements can be damaged as a result of wear or other stresses and can thereby completely lose their security function. To prevent this loss of the security function, the prior art discloses that the security element can be coated with a lacquer after the stamping. However, such a protective lacquer cannot be used on all data carriers, and also wears off after years of use.
The object of the invention is to create a data carrier of the type described above in which the security function of the security element is retained longer, and which can nevertheless be manufactured economically.
The invention teaches a data card of the type described above in which the security element is located between two layers that are laminated to each other and is provided with a protective layer, whereby at least one of the laminated layers is a transparent outer layer. On the data carrier claimed by the invention, the security element is laminated between two layers and thus has extraordinary protection against damage. The protective layer on the security element makes it possible to laminate the security element without damaging it. The security element is subjected to thermal and mechanical stresses during the lamination process. It has now been determined that when there is a protective layer, the lamination can be performed without the formation of cracks and especially microcracks in the extraordinarily thin security element. The security element remains clear and unclouded on account of the presence of the protective layer and is easy visible through the transparent cover layer.
In one development of the invention, the protective layer is a plastic film and in particular a carrier film on which the security element has been vapor deposited. Carrier films of this type of this type are themselves part of the prior art and can be made of polyester, for example. A sealing layer is applied on the underside of the vapor deposited security elements. By means of a hot sealing stamp which is provided with an additional punch contour, the security element is punched out of the carrier film and attached to a layer under the action of heat. In contrast to the methods of the prior art, the punched carrier film remains on the security element and is laminated between two layers on the data carrier claimed by the invention. The carrier film punched out with the security element protects the security element against damage during the lamination process.
In an additional development of the invention, the protective layer is made of a plastic that is essentially not connected with the layer to be laminated thereon. The invention teaches that a loose connection of this type does not adversely affect the stability and adherence of the data carrier in any way.
The data carrier claimed by the invention has in particular layers made of polycarbonate. The problem of damage to the security element is particularly great on polycarbonate data carriers because, in contrast to a card made of PVC, the security element cannot be recessed and is therefore particularly exposed to abrasion. Polycarbonate is suitable for use in the manufacture of, among other things, government identification cards that can remain valid and in use for many years, and for which such security elements are particularly important. On the data carrier claimed by the invention, however, the security element is fully protected against damage and against tampering.
In the method taught by the invention, at least one transparent layer is laminated onto another layer, and a planar security element that bears security information is applied. The invention teaches that the security element is laminated between two layers and is provided with a protective layer that is also laminated between the two layers. In this case, the security element is preferably protected by a protective layer applied to it. Prior to the lamination, the security element is preferably vapor deposited onto a carrier film. This carrier film remains on the security element and during the lamination process forms the above mentioned protective layer.
A particularly effective security against counterfeiting is achieved if, as taught by an additional development of the invention, the security element is a holographic or kinegraphic element. One essential advantage of the invention is that the manufacturing process is no more expensive than the methods of the prior art.